The present invention relates to electrical connecting devices, and more particularly to an electrical connecting device for use in factory assembly of lighting equipment as well as field installation for connecting electrical apparatus together.
Electrical connecting devices are commonly used throughout the electrical industry for connecting electrical leads (wires) together. For example, in connecting a lighting fixture (luminaire) to a ballast, lead wires (hard wired to the ballast) are routed directly to the lamp holders located at opposite ends of the fixture. The lamp holders are typically from two to eight feet apart depending on the length of the lamp for which the fixture is designed.
In replacing an inoperative ballast with a new ballast (i.e. ballast retrofit), the wires from the old ballast are cut in order to remove the old ballast. The wires from the old ballast which remain connected to the lampholders are then electrically connected through an electrical connecting device to the replacement ballast. The types of electrical connecting devices commonly available, however, are both time consuming and tedious to use.
Older, less efficient ballasts are not only replaced when they become inoperative. Rather, in view of much higher efficiencies afforded by newer ballasts, older ballasts, which are not yet inoperable, are today routinely replaced by new, more efficient ballasts (of both the electronic and electromagnetic type). A high demand has therefore been created for an electrical connecting device which is less time consuming and easier to use for purposes of ballast retrofit.
Original equipment manufacturers (OEM's) of lighting fixtures are continually seeking new methods to contain luminaire manufacturing costs. One such method employs modular construction with leadless ballasts and separate wiring harnesses resulting in assembly line automation of the lighting fixture. The electrical connecting device therefore should also be adaptable for use with leadless ballasts and the like, that is, for OEM purposes.
Several different ballast retrofit methods are commonly available. In a first conventional ballast retrofit method, referred to as "wire trap" or "poke-home", wire ends are stripped within a suitable tolerance range and then poked into proper terminal cavities of a multiple cavity connector on the ballast. Such poking typically takes place in a darkened area standing on a ladder with the ballast overhead. Under such conditions, stripping of wire ends within a suitable range of tolerances can be quite difficult. Wire ends must be stripped to a prefixed length in employing the wire trap method. For example, when the length of wire stripped is too small, the wire cannot be properly poked into the terminal cavity. When the length of wire stripped is too large, exposed wire outside of the terminal cavity can result in short circuit and/or electrical shock conditions. The wire trap method is also not suitable for OEM purposes. More particularly, the wire trap method does not by itself provide for a separate wiring harness.
In yet another type of conventional ballast connecting method, barrel terminals are crimped to the ends of the wires and then inserted into a plastic enclosure forming a harness plug. The crimping of these barrels is a precision operation requiring precision tooling. The plug is then inserted into the ballast socket containing mating male pins. The force required in pushing the connector plug into or removing the plug from the connector receptacle during ballast retrofit, however, can damage components within the connector.
These conventional connecting devices are not particularly suitable for purposes of ballast retrofit and ballast manufacture. It is therefore desirable to provide a connecting device which can be easily adapted for connecting electrical wires together whether for purposes of ballast retrofit or manufacture. The connecting device need not and should not be limited to use as a ballast connector and should be suitable for connecting wires of different types of devices together.